1. The Field of the Invention
This invention relates generally to docking stations and port replicators that are used to attach peripheral devices to portable computers. More particularly, this invention concerns a port replicator for selectively attaching peripheral devices to either a portable computer or a desktop computer, i.e., the invention concerns a port replicator that allows for the sharing of peripheral devices between a portable computer and a desktop computer.
2. The Background Art
It is known in the art to use docking stations and port replicators to attach a set of peripheral devices to a portable or laptop computer. When in use, a docking station will have a set of peripheral devices connected to it. In addition, the docking station has a bay for receiving or mechanically coupling to a portable computer. The bay allows the portable computer to be easily connected to or removed from the docking station. When the portable computer is connected to the docking station, the portable computer is electrically connected to the docking station and has access to the peripheral devices that are connected to the docking station.
Docking stations usually provide slots for expansion cards and bays for CD-ROMs and hard drives. Some docking stations have multimedia speakers and a stand or platform for an external monitor to sit upon. Other peripheral devices that can be connected to a docking station are the following: a keyboard, a mouse, a printer, small system computer interface (SCSI) devices, personal computer memory card international association (PCMCIA) adapters, token ring connections, ethernet connections, and other standard computer networking devices. These standard interconnection devices are acknowledged within this application to represent those standards which exist at the date of filing of the present application. In addition, recent developments in docking stations provide means for "hot docking."
Hot docking occurs when a portable computer remains powered on as it is connected to a docking station. The portable computer will acquire complete access to the peripheral devices immediately upon connection to the docking station. Hot docking is desirable because the portable computer does not need to be re-booted to obtain access to the peripherals.
Like docking stations, port replicators are used to attach a set of peripheral devices to a portable or laptop computer. However, port replicators tend to be smaller than docking stations and are not as readily expandable as a docking station. Port replicators perform essentially the same function as a docking station. It is often difficult to distinguish between a docking station and a port replicator. Port replicators will commonly provide connections for the following peripheral devices: a monitor, a keyboard, a mouse, a printer, SCSI devices, PCMCIA devices, ethernet connections, token ring connections, or any combination thereof. Thus, the name "port replicator" is often used interchangeably with the name "docking station."
Also known in the art is a desktop computer used as a docking station. Although this system eliminates the need for a separate docking station or port replicator, a drawback is that the system requires a complex combination of cables and software. Another drawback is that the system requires that a portable computer have a 25-pin parallel port to function with the desktop computer docking station, otherwise, the portable computer will not be compatible with the system. These systems are also known to be susceptible to timing problems and are extremely unreliable.
Although docking stations and port replicators are desirable for the ease with which they enable a user to attach peripherals to a portable computer, the docking stations and port replicators of the prior art lack the ability to share peripherals between a portable computer and a desktop. Thus, docking stations are inconvenient for users of both a portable computer and a desktop computer.
For example, a docking station is undesirable when a user desires to use the same printer for both the portable computer and the desktop computer. To switch the printer from the portable computer to the desktop computer is inconvenient. It requires that the user unplug the printer cable from the docking station and then plug the printer cable into the printer port of the desktop computer. When a user desires to quickly switch the printer from the portable computer to the desktop computer, changing a cable connection can be annoying, time consuming, and sometimes extremely difficult for the user. The cables are often underneath tables or desks and difficult to access. In addition, some users are unfamiliar with computer peripherals and do not understand which cable to unplug and where the cable should be connected.
Of current interest is an improved port replicator that overcomes the disadvantages of the prior art. The present invention is a port replicator that connects a set of peripheral devices to both a portable computer and a desktop computer. Unlike the software handshaking of a network, the port replicator for sharing peripherals provides manually selectable hardware connections for a single set of peripheral devices. Additionally, although devices exist that allow a monitor, keyboard, and mouse to be shared between multiple central processing units (CPUs), until the present invention, no device has been made that provides a means for sharing peripherals between a portable computer and a desktop computer. The port replicator for sharing peripherals overcomes the shortcomings of the prior art and provides a means to selectively connect a set of peripheral devices to both a desktop and a portable computer.